Why SharePoint migration is different in 2026
SharePoint Server 2016 and 2019 have reached the end of mainstream support, Microsoft 365 Copilot now grounds on whatever the migration leaves reachable, and an unprecedented run of mergers and acquisitions has made tenant-to-tenant moves routine. The question is no longer which tool copies files fastest. It is how to sequence, scope and govern the move so the target is auditable, compliant and usable by people and by AI — rather than a faithful copy of the source’s problems. That is the engagement EPC Group has shipped across 6,500+ SharePoint implementations.
The five migration patterns
1. SharePoint on-premises to SharePoint Online
SharePoint 2013, 2016 or 2019 farms migrated to SharePoint Online — the most common pattern. Discovery classifies content and inventories customizations; the target information architecture and permission model are designed; workflows and forms are rebuilt on Power Automate, Power Apps or SPFx or retired; content moves in waves with delta passes and a reconciliation report per wave; a governance baseline ships with the target.
2. Tenant-to-tenant migrations for mergers and acquisitions
Microsoft 365 tenant-to-tenant moves on a deal’s calendar — identity, coexistence, mail, OneDrive, SharePoint, Teams, Power Platform and Power BI — through Day One and the transition-services-agreement exit. EPC Group completed 216+ of them in 2023–2025, covering 1.83 million users. The full program has its own page: Microsoft 365 tenant consolidation for M&A.
3. Google Workspace and Google Drive to SharePoint Online
The usual post-acquisition pattern: a Google-based company integrated into a Microsoft 365 acquirer. Shared drives map to sites, permissions map to the designed model rather than to Google’s, and Docs, Sheets and Slides convert with a reconciliation report. The Prairie View A&M University record in the Evidence Center is this pattern at university scale.
4. Box, Dropbox and consumer OneDrive to SharePoint Online
Storage consolidation onto Microsoft 365 to reduce vendor sprawl and bring content under Purview sensitivity labels, retention and SharePoint Premium document intelligence. Nested folder structures become sites and libraries with owners; sharing links are re-issued under the target policy rather than carried across.
5. Confluence, legacy ECM and file shares to SharePoint Online
Wikis and records systems — Confluence, Documentum, OpenText, FileNet, Hyland — do not map one-to-one onto SharePoint, so the information architecture is redesigned, not mirrored, and specialized connectors move the content with its metadata. File shares are the simplest source and the most common place to find twenty years of content nobody has classified; discovery decides what moves, what archives and what is deleted.
The six ways SharePoint migrations fail — and what the engagement does about each
Lift-and-shift of the source mess
Copying every site, every version and every broken permission into SharePoint Online reproduces the problem at higher cost. The remedy is a discovery that classifies content (active, archive, delete), a target information architecture, and a permission model designed before the first byte moves.
Permissions as an afterthought
Item-level overrides, orphaned groups, anonymous and anyone links, and external sharing carried across unexamined are the largest source of post-migration tickets — and, once Copilot arrives, of exposure. The remedy is enumeration, classification and remediation before the wave, with Restricted Content Discovery where remediation lags.
Workflows and customizations discovered at cutover
SharePoint Designer workflows, InfoPath forms, farm solutions and custom web parts have no direct equivalent online. The remedy is an inventory in discovery, a rebuild plan (Power Automate, Power Apps, SPFx or retirement) with owners, and a decision on each before its site is scheduled.
One big-bang weekend
A single cutover of everything leaves no room to learn. The remedy is waves by business unit with a pilot wave first, delta passes so the source stays usable until the wave is verified, and a reconciliation report per wave that the business signs.
Nobody owns the target
A migrated tenant with no governance — no site-provisioning process, no retention, no sensitivity labels, no owners — degrades within a year. The remedy is a governance baseline delivered with the migration and a support model that keeps it.
The migration-only vendor
A vendor whose product is the move is done when the bits are copied. The information architecture, the permission model, the rebuilt workflows, the governance and the Copilot readiness that determine whether the target is worth having are out of scope. EPC Group scopes those in, because that is where migrations succeed or fail.
The cutover, wave by wave
- 1Freeze window agreed with the business unit; the source set read-only for the wave's sites
- 2Final delta pass; the reconciliation report compares item counts, versions, permissions and metadata source-to-target
- 3Permissions verified against the designed model, not against the source
- 4Redirects and links updated; the service-desk script and the user communication go out
- 5Hypercare for the wave — a named engineer, a defined response time, a daily issues review
- 6Business sign-off per wave; the source archive retained on the agreed schedule, then decommissioned with evidence
A pilot wave goes first — one business unit, real content, real users — so the runbook is corrected on a small population before the large ones move.
Support after the move
Every migration ships with a governance baseline: a site-provisioning process with owners, retention and sensitivity labels applied, an external-sharing policy, and the permission model documented. The same architects can then run it under the Managed Microsoft Support tiers — SharePoint administration, permission audits, governance reviews and incident response — and the Copilot readiness assessment picks up where the migration leaves off, because the permission model and labels it leaves behind are what Copilot grounds on.
EPC Group versus a migration-only vendor
A migration-only vendor sells the move: a tool, a schedule, a count of items copied. It is done when the bits land. EPC Group sells the outcome the move is supposed to produce — a SharePoint Online estate with a designed information architecture, a permission model that survives Copilot, workflows that run, a governance baseline someone owns, and the compliance evidence a regulated industry needs — and scopes the move as one part of that. The difference shows in the discovery (classification, not just counting), in the waves (reconciled and signed, not just completed) and in what is left behind (a governed tenant, not a copy).
Why EPC Group
- Scale on exactly this work: 6,500+ SharePoint implementations since 1997; 216+ M&A tenant migrations covering 1.83 million users in 2023–2025; 11,000+ enterprise engagements.
- The method is published. Founder Errin O’Connor is the author of four Microsoft technology books (Microsoft Press; Sams/Pearson), three of them on SharePoint.
- Microsoft Solutions Partner holding all six designations, including Modern Work and Security; G2 Leader — seven consecutive quarters (4.4/5 on G2).
- Contracted records, not logos. Redacted purchase orders, statements of work and countersignatures in the EPC Group Evidence Center, including the Tarleton State University cross-tenant migration (2021) and the Prairie View A&M University Google Workspace migration (2020).
- Senior architect on every statement of work — the person who scopes the migration leads it through the last wave.
FAQ
What SharePoint migration services does EPC Group offer?
Five migration patterns, each with its own playbook: SharePoint on-premises 2013, 2016 or 2019 to SharePoint Online (content, structure, workflows, permissions); tenant-to-tenant Microsoft 365 migrations for mergers and acquisitions (216+ completed in 2023–2025, 1.83 million users); Google Workspace and Google Drive to SharePoint Online; Box, Dropbox and consumer OneDrive to SharePoint Online; and Confluence, legacy ECM and file shares to SharePoint Online. The practice sits on 6,500+ SharePoint implementations since 1997.
How long does an enterprise SharePoint migration take?
It depends on volume, source complexity and how much of the target has to be designed rather than copied. A single modern source under a terabyte runs a few weeks; a multi-site on-premises farm with governance redesign runs two to three months in waves; a large regulated estate with tens of thousands of users runs three to four months with a pilot wave first. Tenant-to-tenant M&A moves follow the deal calendar. The scoping call gives you the estimate in writing, with the assumptions.
What does an enterprise SharePoint migration cost?
Engagements are fixed-scope and priced after a scoping call that confirms data volume, source complexity, the permission and governance work, and the regulated-industry controls in scope; there is no rate card. Microsoft licensing and migration tooling are quoted at list. Contracted engagement records for comparable migrations are published, redacted, in the EPC Group Evidence Center.
What migration tools does EPC Group use?
Whatever the scenario needs: Microsoft FastTrack where the tenant is eligible; the Microsoft SharePoint Migration Tool and Microsoft Mover for straightforward file-share, on-premises and Google sources; ShareGate for complex permissions and tenant-to-tenant moves; AvePoint or Quest where the estate or the M&A timeline calls for them; custom connectors for legacy ECM systems. The tool is chosen in discovery, and the reconciliation report is produced the same way regardless of tool.
How are permissions handled during migration?
They are the number-one source of post-migration tickets, so they are handled first: discovery enumerates every permission — SharePoint groups, directory groups, item-level overrides, sharing links, anonymous and external access; classification flags broken inheritance, orphaned principals and oversharing; the target permission model is designed; and remediation happens before the wave. Where the estate is too large to remediate before Copilot is enabled, Restricted Content Discovery keeps the long tail out of the model until it is fixed.
How does SharePoint migration work for mergers and acquisitions?
M&A tenant-to-tenant moves are a distinct discipline with their own page — Microsoft 365 tenant consolidation for M&A — covering discovery across both tenants, the identity decision, coexistence, data movement in waves, Day One and the transition-services-agreement exit. The SharePoint workstream inside it follows the same playbook as any migration, on the deal's calendar. EPC Group completed 216+ such migrations in 2023–2025.
What about Google Workspace, Box, Dropbox or Confluence sources?
Common, especially after an acquisition of a Google-based company or a consolidation of file storage onto Microsoft 365. Google Drive moves through Microsoft Mover or ShareGate with permission mapping for shared drives; Box and Dropbox through their export paths into the SharePoint Migration Tool or ShareGate; Confluence and legacy ECM (Documentum, OpenText, FileNet, Hyland) through specialized connectors with the information architecture redesigned rather than mirrored, because a wiki or a records system does not map one-to-one onto SharePoint.
How are regulated-industry migrations handled?
The controls travel with the content: sensitivity labels and retention preserved or re-applied, eDiscovery holds honored across the move, audit trails retained, and the validation and documentation each regime expects — HIPAA, FINRA and SEC record-keeping, FedRAMP and CMMC for government and defense, 21 CFR Part 11 for life sciences — produced as part of the wave, not reconstructed afterward.
What happens after the migration?
A governance baseline ships with the migration — site provisioning, ownership, retention, labels, external-sharing policy — and the same architects can run it under the Managed Microsoft Support tiers: SharePoint administration, permission audits, governance reviews and incident response. Copilot readiness is the natural next step, because the permission model and labels the migration leaves behind are what Copilot grounds on.
Why EPC Group rather than a migration-only vendor?
Because the move is the smaller half of the work. A migration-only vendor is done when the bits are copied; the information architecture, the permission model, the rebuilt workflows, the governance and the Copilot readiness that decide whether the target is worth having are out of its scope. EPC Group scopes them in, on 6,500+ SharePoint implementations since 1997, with founder Errin O'Connor's four Microsoft technology books (Microsoft Press; Sams/Pearson) behind the method and the architect who scopes the migration leading it.
Related EPC Group services
- • Microsoft 365 tenant consolidation for M&A
- • M&A Microsoft 365 tenant migration
- • SharePoint consulting (hub)
- • SharePoint governance consulting
- • SharePoint permissions and oversharing audit
- • SharePoint governance health check
- • SharePoint intranet consulting
- • SharePoint multilingual intranet implementation
- • The September 2026 SharePoint governance checklist: library metadata for Copilot and Purview archive
- • Microsoft 365 Copilot readiness assessment (TAR-8)
- • Microsoft 365 consulting (hub)
- • EPC Group Evidence Center — contracted engagement records
- • EPC Group client reviews across public platforms
Book the migration scoping call
Thirty minutes with the architect who will lead the migration. Bring what you know about the source; you leave with the pattern, the wave plan and a written estimate with its assumptions.
Deep-Dive Guides
Related enterprise references from the EPC Group knowledge base: